Creating Light AOVs & Custom Light AOVs in Maya Arnold | Tutorial

all right so um this session we want to talk about aovs and how we can create um like aovs in maya so that it helps to output them for usage in new or compositing later on okay so there's a documentation of aovs um in the maya documents and you guys can feel free to read about it so basically it outputs different layers or component of the image separately so that you can tweak them separately in nuke later on for example the diffuse or the specular or even your polite different aovs okay what i mean by that is okay for example i i set up a scene like that right then i want to um so in my renders i only get a beauty so there's no aovs within them so i can't tell what my my key light is actually contributing to this character i can't um see them separately um within the aovs okay so what i can do is i'll select my light okay for example this is my key light okay it's key one because i duplicated my original one to to just place it and give a more dramatic uplighting look okay so key light okay go into the light shape scroll down you'll see this aov like group okay so under here you need to give it a name ideally we always keep it the same as your naming as your like so for example we keep this as key one okay because i i don't do or maybe i just change this name so up uh kick my kick like okay for example and this will be kick okay so this is the first step you need to do you set the aov like group second you'll go into your render settings aovs click on add custom okay you'll type in caps rgba underscore the like group name that you entered okay let me repeat myself you will set your light group so for example after you rename your likes go to light group and set a name here and go to render settings aovs add custom caps rgba underscore the like group name that you entered not the like name okay so this will be kick instead of lgt underscore kick right so it will be just like group name kick okay create okay that way we get a lv for this um our kick like so now if we were to re-render okay i'll just stop um a little bit noisy and you click here you see that it creates a different aov so now if we click this oh it's black let's see what's happening um it's black just one moment let me just troubleshoot what's happening so my kick like tribute so it's kick there's spell wrong k i c k k i c k i ah come on um okay i name it rg rbga okay so let me just delete and recreate so rgba underscore kick okay then render again so there you go so under this rgb and the score kick i get my kick light contribution and you can see that in my beauty i got my rims as well so that's my kick then of course you want to expose all these aovs for all your likes so what you can do is uh for example my room like okay i have two so say because i do not want to um i want to have them in a single aov what i can do is i'll go to my rim light go to my attribute editor okay i'll name it the rim okay if the light group name are the same the the lights will be combined and output in a single aov okay so now it's here i only select this screen left frame okay so if i were to create the aov for it rgb is called rim and i render okay i go to my rim aov i get my screen left one right but say i want to merge my screen right rim into this aov as well i don't want to generate so many uvs okay i will go to my light group and name it the same as my rim the screen left frame so i name it rim right so i'll put it the same here and then right now if i re-render again you can see that this rim aovs consists of both the rim legs okay so yep so basically that is the the gis of course the basic on how you can separate out your different legs into different aovs so in nuke you can shuffle them out expose them up and down shift the colors if you want or even animate them if you want um in nuke so that's the basic for example um you know you want to go more in depth you want to do some advanced stuff you want to export your for example your your kick light and you want to split this aov into the different components of this uh on of this character so for example i want this now this kick like will shows me everything like the diffuse the specular or everything combined into one right because it's just rgb and for example if i want to just see the diffuse component and not the specular component um i can i can do very custom stuff so what i can do is i can go into my render settings okay for example i want to create a kick diffuse okay so i'll create a blank aov which for me is too custom i'll go into the attribute editor okay under this custom aov there's this like path expression in short they call it the lpe which i use to generate all these aovs for the likes okay if you click on this button here it will show you a lot of things that you can use because they are all in different you know languages that you probably will not remember so if you need them you can click here and then click whatever you need alternatively you can't go into the oh not this sorry the maya documents again and look for this lp documentation and then inside there again you get all your for example you got your d fields and you get the the code that you need right okay so how we can use this so now we mentioned that we only want to see the like diffuse component right so um in the document oh sorry not this one in the documentation the diffuse is this okay i'll just copy this okay paste here okay so star will grab all the lights and just output it as the the generic diffuse component of every light combined into one but for example i only want to see this kick likes diffuse contribution so what i can do is i can instead of putting this star right i can add this i can't remember the name of this symbol this triangle thing then l dot quotes this kick the name of the light group and then close it okay um if i remember correctly the syntax should be like that let's just do a test render and hopefully it works so keep the fields there you go so this is the diffuse component um of the the character so as you can see the diffuse component looks a bit wonky i suspect mainly our the shader is reacting i mean the light is reacting to the specular instead so again we can we can prove it so we can create the kick specular okay then we can go into the attribute of editor of this aov okay like path expression with i mean i can just quickly see it from here there's this specular this one okay we will input in here again we want to remove this um star and then change it to um the light that we are using only okay so we can put like things like uh l dot open key and not kick like that okay then just do a quick render go into the specular component okay this is special component i think my diffuses have having some issues let me just double check my diffuse um um lpe so l dot kick rd okay let's just double check okay c rd dot okay that looks correct so maybe it's just really um let me just put this dot behind check again okay so i i had the wrong syntax or the wrong way of doing this early on um okay i will just use a notepad so of you guys can see because the text might be very small in the screen okay so by default um by default the diffuse component lp is where is it the fields here so it's like that right so the diffuse component technically is like that but this is grabbing all the lights in the scene um to generate this aov so what i did is uh what we need to do is we need to add in this and specifically point to just our kick light right so we need to input in this before this dot okay and if you have other likes that you want to do like a rim light you just need to replace this name here okay so why not just try it um can i remove this so now the diffuse component specular component and the light source itself so um everything okay so now i want to split up my rim lights contribution as well so same thing we go to our aovs we'll do rim diffuse and rim specular okay one thing to note um outputting many aovs is uh a good thing but if you are outputting all these aovs that are not being used like you are just output uploading for fun for your personal preference you want to see them but actually they are not being used um it's not a good thing because it takes up render time and no the more aovs you add the more render time it takes to to generate your renders so keep it to what what you need only so by default i would recommend just the rgba that should give you more than enough to to tweak um income but for for some reason you need a specific like to tweak the specular differently go ahead and do it but do not do for every likes and export uh export uh all the components for example the subsurface the the coating the transmissions the reflection or whatever um things that you can add don't don't just put all of them inside okay okay so now the fuse we can go to here copy the the kick like that we already set up go into the the rim and paste it change the kick to grip then we can do the same thing for the specular will copy it then go to specular and rename this to rip okay now if we were to render okay we still get the beauty of everything then if you look into the rim diffuse this is the diffuse component so you can see um without specular it looks pretty nice then with the specular these are the very high pings or highlights that you are seeing on the character yeah so um i mean if you are if you really are into this all this kind of aovs um lp thing you can write scripts like python scripts or mail scripts uh probably i can do a demo in a future um episodes but we can of course write scripts um to query the scene how many likes are there and then automatically create all these aovs by default so you don't need to go into render settings at them in manually or changing the lp manually you can use a script to generate them by default and that'll be great that will showcase that you are a very efficient artist um and you really think through the workflow because all these kind of things it's you set it up once and you can reuse it again and again um in the future right instead of no i mean that is like what they said you you suffer first and you create a tool and then you enjoy it for the rest of the your life with the two that you created or you just have to suffer every every time with creating the aovs manually yep so that's it this session is about this aov and hopefully it's helpful to all of you guys thank you

Channel: TOILSTORY

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Keywords: TOILSTORY, THETOILSTORY, showcase, designer, designertoys, autodesk, maya, arnold, rendering, lighting, compositing, vfx, visual effects, cg, cgi, computer graphics, render, command line, cmd, windows, win, windows 10, win10, tips, tip, tricks, tips and tricks, useful, students, 3dsense, media school, 3ds, 3d, tutorial, demo, light, pixar, kitchen, scene, shot, beauty, dof, nuke, foundry, render layers, render passes, composite, breakdown, demoreel, portfolio, knowledge, cryptomatte, settings, samples, education, learn, singapore

Id: dmVHv9l9Iho

Length: 15min 0sec (900 seconds)

Published: Fri Aug 06 2021